732298-15-6

Upstream product

• 35323-91-2 (+)-epicatechin 
• 100-39-0 benzyl bromide 
• 732298-14-5 (-)-(2S)-5,7-bis(benzyloxy)-2-[3,4-bis(benzyloxy)phenyl]chroman-3-one 
• 67-63-0 isopropyl alcohol 
• 5447-02-9 3,4-dibenzyloxybenzaldehyde 
• 63604-98-8 1,3-dibenzylphloroglucinol 
• 203571-40-8 3-(3,4-bis-benzyloxy-phenyl)-acrylic acid ethyl ester 
• 20728-73-8 5,7,3',4'-tetra-O-benzyl-(+)-catechin 
• 490-46-0 (2R,3R)-2-(3,4-dihydroxyphenyl)-3,4-dihydro-1[2H]-benzopyran-3,5,7-triol 
• 100-44-7 benzyl chloride 
• 1392190-80-5 pentabenzylated cyanidin 
• 13157-90-9 2-[3,4-bis(phenylmethoxy)phenyl]-3,5,7-tris(phenylmethoxy)chromen-4-one 
• 1392108-94-9 (R)-(2S,3S)-5,7-bis(benzyloxy)-2-(3’,4’bis(benzyloxy)phenyl)chroman-3-yl 2-methoxy-2-phenylacetate 
• 1392108-91-6 2-[3,4-bis(phenylmethoxy)phenyl]-3,5,7-tris(phenylmethoxy)-2H-1-benzopyran 

Downstream Products

• 732298-16-7 (+)-(2S,3S)-5,7-bis(benzyloxy)-2-[3,4-bis(benzyloxy)phenyl]chroman-3-yl 3,4,5-tris(benzyloxy)benzoate 
• 35323-91-2 (+)-epicatechin 

Relevant academic research and scientific papers

The flavan-isoflavan rearrangement: Bioinspired synthetic access to isoflavonoids via 1,2-shift-alkylation sequence

An approach to 2-substituted isoflavonoids is reported based on the 1,2-shift of the aryl group in the catechin skeleton followed by the in situ alkylation. Synthesis of (-)-equol, a natural isoflavan with estrogenic activities, was achieved.

NOVEL PROCESS FOR SYNTHESIS OF POLYPHENOLS

The present invention provides synthetic processes for preparing racemic and/or optically pure epicatechin, epigallocatechin and related polyphenols as such or as their variously functionalized derivatives. A principle objective of the disclosure is to provide a new and useful method of synthesis to obtain polyphenols in isomerically pure and/or racemic forms.

A NOVEL PROCESS FOR SYNTHESIS OF POLYPHENOLS

The present invention provides synthetic processes for preparing racemic and/or optically pure epicatechin, epigallocatechin and related polyphenols as such or as their variously functionalized derivatives.

PREPARATION OF (+)-CATECHIN, (-)-EPICATECHIN, (-)-CATECHIN, (+)-EPICATECHIN, AND THEIR 5,7,3',4'-TETRA-O-BENZYL ANALOGUES

Processes for preparing racemic mixtures of 5,7,3',4'-tetra-O-benzyl-(±)-catechin and (±)-epicatechin involves (i) condensing 2-hydroxy-4,6-bis(benzyloxy)-acetophenone and 3,4-bis(benzyloxy)benzaldehyde, cyclizing the resulting compound, oxidizing the resulting compound; (ii) dihydroxylating (E)-3-(3',4'-bis(benzyloxy)phenyl)prop-2-ene-1 -ol and reducing the 1 ,2-diol; or (iii) coupling 3,5-bis(benzyloxy)phenol with (￡)-3,5-bis(benzyloxy)-2-(3',4'-bis(benzyloxy)phenyl)allyl)phenol and cyclizing the resulting chalcone. A process for preparing the benzylated epimers of catechin and epicatechin involves seven steps. 3,4-Bis(benzyloxy)benzaldehyde is coupled with 2-hydroxy-4,6-benzyloxy-acetophenone to form a chalcone. The chalcone is selectively reduced to an alkene. The phenolic group of the alkene is protected. The protected alkene is asymetrically dihydroxylated. The resulting compound is deprotected, cyclized, and finally hydrolyzed. Epimers resulting from these processes are chemically resolved or separated by chiral high pressure liquid chromatography. Also disclosed is a method for preparing enantiomerically pure 5,7,3',4'-tetra-O-benzyl-(+)-catechin from a racemic mixture using dibenzoyl-L-tartaric acid monomethyl ester. Further, disclosed is an improved process for preparing dibenzoyl-L-tartaric acid monomethyl ester.

Study of the green tea polyphenols catechin-3-gallate (CG) and epicatechin-3-gallate (ECG) as proteasome inhibitors

The green tea polyphenol catechin-3-gallate (CG) and epicatechin-3-gallate (ECG) were synthesized enantioselectively via a Sharpless hydroxylation reaction followed by a diastereoselective cyclization. Their potencies to inhibit the proteasome activity were measured. The unnatural enantiomers were found to be equally potent to the natural compounds.

Resistance factors to grey mould in grape berries: Identification of some phenolics inhibitors of Botrytis cinerea stilbene oxidase

Grey mould caused by Botrytis cinerea is one of the most important diseases of grapes. Between bloom and veraison, grape berries are resistant to B. cinerea, although they can harbour the pathogen without any visible signs of disease development. After veraison, B. cinerea can produce disease in susceptible grape varieties (e.g. Gamay), but remains quiescent in resistant varieties (e.g. Gamaret). Pathogen resistance in the quiescent stage is not yet fully understood, but is thought to involve multiple parameters including chemical and mechanical factors. The pathogenesis of B. cinerea is essentially linked to excretion of lyric enzymes such as polyphenoloxidases or laccases. One lytic enzyme, stilbene oxidase, can detoxify grape stilbenic phytoalexins, destroying the grapes' defence mechanisms and allowing the fungus to grow. Some constitutive grape berry phenolic compounds, however, strongly inhibit stilbene oxidase activity. Constitutive berry phenolic compounds were isolated from Gamay and Gamaret varieties and their biological activities, concentrations and chemical structures were comparatively analysed. Catechin, epicatechin-3-O-gallate, trans-caftaric, trans- and cis-coutaric and trans-coumaric acids, taxifoline- 3-O-rhamnoside and quercetine-3-O-glucuronide were identified as potent stilbene oxidase inhibitors. High concentrations of some of those compounds could be closely involved in the persistence of the quiescent stage of B. cinerea, between bloom and veraison in all grape varieties and after veraison in resistant varieties.